tests, plot doc addition
anotehr create.bins issue, Jason Roberts proposed fix
don't need to specify obs.table, tests for this
fixed bug that crashed binning when distances were NA
check that effort data is consistent per-sample
clarification that stratification only happens in dht
Fixed bug in binning.

Truncation not applied during the binning of the data meant that users
had to truncate manually before calling ds(). This has been changed so
truncation of the distances happens at binning time.
more tests for ds() and dht() against mrds
Setting order=0 is equivalent to adjustment=NULL to specify a detection
function without adjustments. (Eric Rexstad brought this to my
attention.)
previous condition for order=0 prevented automatic adjustment selection,
fixed
Travis continuous integration experiment